Grinding-machine



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GRINDING MACHINE. No. 565,644. Patented Aug. 11, 1896.

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I. W. TAYLOR. GRINDING MACHINE.

No. 565,644. m Patented Aug. 11, 1896.

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GRINDING MACHINE;

No. 565,644. PatentedvAug. 11, 1896.

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, GRINDING MACHINE. No. 565,644. Patented Aug. 11, 1896.

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' GBINDINGMAGHINE. No. 565,644. Patentedlug. 11, 1896.

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" NITED" STATES FREDERICK \V. TAYLOR, OF PHILADELPHIA, PENNSYLVANIA.

GRINDING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 565,644, dated August 11, 1896.

Application filed December 17,1886. Serial No. 221,865. (No model.)

To all whom it may concern:

Be it known that I, FREDERICK W. TAYLOR, a citizen of the United States, residing in the city and county of Philadelphia, in the State of Pennsylvania, have invented eertain'new and useful Improvements in Grinding-Machines, of which the following is a specification..

The object of my invention, which is particularly designed for grinding steel tools or cutters used in turning and boring metal, is to provide a machine of simple'and inexpen+ sive construction by the operation of which the toolsor other objects may be so ground or dressed as to uniformly correspond in form or contour with each other and with given standard surfaces.

The new and useful features of my said invention are fully set out in the claims which conclude this specification.

Reference being had to the accompanying drawings, formingwpart of this specification, in which similar numerals of reference inclicate corresponding parts throughout the several views, Figure 1 is a side View, partly in elevation and partly in section, through the table of a grinding-machine embodying my invention. Fig. 2 is a plan or top view of the same. Fig. 3 is a front elevation of the same. Fig. 4 is a vertical central section taken transversely through the machine on the line a; a; of Fig. 2, some of the parts being shown in elevation. Fig. 5 is a partial side elevation showing the slide-table, grindstone, and toolholder. Fig. 6 is a partial planview illustratin g a modification of the tool-holder. Fig. 7 is a view in perspective of the tool-holder shown in Fig. 5. Fig. 8 is a similar View of the tool-holder shown in Fig. 6. Fig. 9 is a view in perspective of a modification of the grinding-machine shown in Fig. 1. Fig. 10 is a similar view of a further modification, shown fragmentarily. Fig. 11 is a plan view of a fragment of a further modification, a portion being given in horizontal section. Fig. 11 is a view in perspective of a further modification of the detail illustrated in Fig. 11. Fig.12 is aperspective view of afurther modification, a part of the table being represented as broken away for the sake of showing a detail of its lower part. In this latter figure,as also in Fig. 11", the relative positions of the grindstone to parts illustrated is indicated by broken-line outlines of segments of the grindstone.

In general in the drawings the bed of the machine, which is preferably in the form of a vertical standard or pedestal surmounted bya horizontal cap or face plate, is designated by the numeral 7. Upon this the main or driving shaft 2, which carries the grindstone or emery-wheel 3, by which the grinding operation is performed, is mounted in bearings 6, which bearings, as shown in Figs.

1 to 4, are preferably formed in or fixed to an auxiliary frame 67, fitted to slide in guides or ways on the cap of frame 7 and being adapted to be moved or fed backward orforward thereon as may be required during the grinding operation. The shaft 2, being provided with a fixed longitudinal spline or feather 71 upon one of its outer or projecting ends, (see lefthand end of shaft 2, Fig. 4,) is adapted to be rotated by a belt passing around a drive-pulley 1, so fitted upon this feather-provided end.

of shaft 2 that the latter shall be rotatably driven thereby while also having the capacity of endwise movement through said pulley. Intermediate of its bearings in the frame slide-block 67 the g'rindstone or emery-wheel 3 is fixed upon the shaft 2 by means of a nut 45, movable flange-plates 5, and fixed flangeplate 5 in the ordinary manner.

In order successively to present different portions of the face of the grindstone to the article which is being'ground, and thereby tend to maintain the grindstone in its preferred truly cylindrical form, 1 preferably provide that the said grindstone shall not only be rotated, but shall also receive a continuous endwise reciprocating movement. To carry this into effect, I preferably pro vide, as shown in Figs. 1 to 4, inclusive, that the grindstone shall have its aforesaid shaft 2 provided with sufficiently long and uniformly cylindrical journal parts to admit of a range of endwise reciprocations embracing one range substantially equal to the breadth of the face of said stone. This I accomplish by the following swash-motion mechanism, to wit: A shaft 9, appropriately collared against endwise reciprocation, is mounted in bearings 10 of a post or standard fixed upon the auxiliary adjustable frame 67,

ICO

such shaft carrying a fixed drive-pulley 8, by which it may receive motion from a pulley 011 a suitable counter-shaft, and by this means, concurrently with the driving of the main shaft 2, impart rotary motion to a disk-cam 11,which, having a cylindrical periphery with a curved body, is fixed upon a projecting outer end of the shaft 9 in such wise as to assume an angular position to the axial line thereof in the manner best comprehended by refer-' ence to Figs. 2, 3, and 1, scriatz'm. A lever 14 is pivoted to a projection 10 on the standard which carries the bearings of the shaft 9 by a pin 16, which may be passed through any one of a series of holes 16 in the projection 10 and through the corresponding hole of a similar series in the lever 14. A pair of friction-rollers 12, journaled 011 pins 13, fixed vertically in the upper end of lever 14, bear against opposite sides of the aforesaid cam or swash plate 11, by the rotation of which the lever 14 is oscillated upon the pin 16. The degree of movement of the lever 14 at its lower end, which is coupled to the grindstoneshaft, as next described, is greater or less according as its pivot -pin 16 aforesaid is placed at a greater or less distance from the cam 11. The lower end of lever 14 is forked so as to pass on each side of shaft 2, and a pin or bolt is fixed at each of its forked ends, upon which pin are journaled curved shoes, which fit into a corresponding peripheral groove in the shaft 2 and find a bearing against the sides thereof. The oscillating movement of the lever 14, produced by the rotation of the drive-pulley 8, effects the reciprocation of the grindstone-shaft and grindstone without interfering with their rotation, the speed of reciprocation being preferably, and according to the contour of the cam 11 thus illustrated in Figs. 1 to 4, substantially uniform at all points of the endwise movement of the grindstone. I also contrive to disconnect such swash-motion mechanism, when desired, by removing the driving-belt from the pulley 8, and then preventing accidental endwise movement of the grindstone, which its aforesaid preferred elongated shaftjournals might permit, by inserting a pair of pins through two pairs of the registering holes in the lever 14 and projection 10.

For the purpose of protecting those portions of the journals of the grindstone-shaft2 which are protruded beyond their bearings during the reciprocating movements of said shaft from access of dust and grit I provide a se ries of telescoping covers, which are shown in Fig. 4 only, and by which the journals are completely incased at all points of the longi tudinal traverse of the shaft 2. A cylindrical cover 68 is fixed upon each end of the grindstone-shaft bearings 6 concentric with the shaft 2. Said covers have outwardly-projecting flanges or rims on their outer ends, which fit freely within cylindrical covers 69, of such length and secured upon the shaft 2 at such distances beyond the covers 68 as to admit of their constantly inclosing the end rims of the cover 68 during the reciprocations of the shaft. The ends of the covers 69 are provided wit-h inwardly-turned rims or flanges, which fit neatly around the cover 68 and serve as an additional bar to the access of foreign matter.

A pair of dovetailed guides or ways 18 is cast upon or secured rigidly to the top of the frame 7 of the machine at right angles to the plane of the grindstone-shaft 2, and a saddle or support 17 of a tool-holder table 19 is fitted to traverse on said guides 18 toward and from the grindstone-shaft, and also to be clamped in desired position on the guides 18 by gibs and set-screws, as indicated'in Fig. 3. In order that the surface on which the object to be ground is supported may be brought to any desired angle with the face of the grindstone 3, the tool-holder table 19, which comprises said surface, is mounted upon the top of the said preferably adjustable saddle 17 in such manner that the said tables angle therewith may be varied as desired. For this reason I have shown in the preferred form, Figs. 1 to 4, the table 19 resting by a cylindrical projection or journal 20 on its under side (shown in section in Fig. 1 and in dotted outline in Fig. 5) in a corresponding transverse groove orhollow in saddle 17, and adapted to be tilted about the journal 20 in order to bring it to a proper inclination and adjustment by a screw 21 at its front and a pair of screws 23 at its rear end. The front screw 21 is for this purpose provided with a head in the form of a segment of a sphere, which fits into a corresponding socket in the table 19, whence the body of the screw passes through suitably-relieved holes in both the table 19 and saddle 17, the thread engaging a spherical-faced nut fitting in a corresponding socket on the lower side of the saddle. The screw 21 is adapted to be rotated by the hand-wheel 22. The rear screws 23 are pivoted at their lower ends to the saddle 17, and, passing through slotted holes in the table 19, are provided with nuts 24 at their upper ends, by which a downward draft may be exerted on the rear end of the table.

In order to admit of the reciprocatory traverse of the grindstone when the above-described swash-motion mechanism is in operation, and also to fetch the table or tool-holder IIO supporting surface well around the sides of the grindstone within the range of the table 17, as in many grinding operations it is desirable to do with my improved machine, a gap or recess of a width adapted to admit the maximum of said reciprocatory movement of the grindstone 3 is formed in the rear end of the table 19, the side portions of which, as shown in Figs. 1 and 2, then project and normally pass inwardly on either side of the stone for some little distance; also, in order to provide a preferably adjustable guiding surface representing the grinding-face of the stone, which in this case is its tread or cylin- 7 ever arrived at the relative positions of the drical periphery and against which is .to be applied a former or templet representing the contour to which it is desired to grind the tool or other articles subject to the action of the grindstone, I secure on each of the rear side portions of the table 19 aforesaid a vertical post or standard 19, to which a guideplate carrier 25 is fitted so as to traverse toward and from the vertical axial plane of the grindstone 3, by lateral flanges, which, fitting recesses formed in the heads 19 of the post 19, serve to guide said carrier-plate, when traversed in either direction by a screw 26, engaging a nut in the guide-plate carrier 25 and rotating freely without end movement in a bearing projection from the inner end of one of the post-heads 19. To this carrier 25 I attach a guide-plate 27, the front face of which, as shown in Fig. 5, constitutes the aforesaid adjustable guiding-surface representing the active part of the grindstone aforesaid. The mode of attachment between the carrier 25 and guide-plate 27 being in the manner of a mortised guide and a prismatic sliding part, plate 27, the said plate may be caused to approach or recede from the surface of the table 19 by a feed-screw 28, rotating freely in a bearing on the upper end of the guide-plate 27 without end movement and engaging a nut formed in or attached to the guide-plate carrier 25. It will be obvious that in this preferred mode of construction the guide-plate 27, which has a substantially plain surface of application, as aforesaid, always maintains a definite angle to the upper or supporting surface of the grinding-table 19 whatever be the angle at which that table is set in relation to the stone; that is to say, the guide-plate is in this case parallel to each element of the grinding-face of the grindstone and preferably also free to be moved either toward or away from said stone or toward or away from the surface of the grinding-table, as the exigencies of the grinding operation in hand at any time may dictate.

In order to prepare for the operation of the machine, the tool or other article to be ground, 36, is clamped within a suitable tool-holder 35, a proper relation being maintained to a templot or former 39, which being substantially of the outline to which it is desired to grind and finish the surface of the tool or other article 36 is likewise clamped in said tool holder. A convenient device for obtaining such proper relation of the tool and templet in the tool-holder forming the subject-matter of an application lately filed by me in the United States Patent Ofiice and entitled An adjusting device for grinding-machines, Serial No. 237,061, dated May 4, 1887, is here no further referred to, save only to state that how templet 39 and piece of work 36 in the toolholder 35 in the use of the above-described preferred form of my machine are such that when the tool-holder is placed upon the table 19 and the surface of the templet 39 applied against the guide-plate 27 the surface of the piece of work 36 will come within range of or bear against the periphery of the grindstone 3, and the templet 39 being held continuously against the guide-plate 27 and the tool-holder 35 being moved about by the operator on the surface of the table 19, so as to successively expose different portions of the piece of work 36 to the action of the grindstone, preferably in the manner hereinafter more particularly described, the piece of work 36 will be ground to the desired form, corresponding with that of the face of the templet or former 39.,

In order to prevent undue heating of the grindstone and the piece of work in the grinding operation of the aforesaid preferred form of my grinding-machine, their surfaces are subjected to the cooling action of a jet of water applied by a suitable pipe, andfor this purpose I have illustrated in Figs. 1 and 2 a small centrifugal pump 7 4, which is fixed upon the lower portion of the frame 7 and adapted to be rotated by a belt '72, passing around a pulley 73 on the shaft of the pump and also around a pulley on the main shaft 2.

ater is supplied to the pump by a suctionpipe 75, and is discharged between the faces of the grindstone and of the piece of work being ground by a delivery-pipe 7 6.

In the proper operation of the machine, and

to this part of the specification I would call special attention, the piece of work 36 and the templet 39 having been properly adjusted and clamped in their respective positions in the tool-holder 35, as aforesaid, the latter, which has a substantially plain foot or bearing-surface, is placed upon the table 19. A small pin 45 on the tool-holders lower side, being inserted into one of a series of slots 7 O in the surface of the table 19, then prefer-7 ably serves to prevent such undue lateral movement of the tool-holder as might otherwise result from the above-described pre-. ferred reciprocating movement of the grindstone when acting upon the piece of work. Such small pin or other equivalent device for preventing undue lateral movement of the tool-holder, while it may at times assist the operator in the manner of a fulcrum bearing on the slot 70 when in the act of swiveling the tool-holder in the plane defined by the table 19, I shall call a side-motion stop.

I provide, further, in the preferred form of my machine not only that the tool-holder 35 may be applied by hand-pressure within the range of the grindstone 3 when supported on the table 19, but also by means of what I shall herein designate as a uniform-pressure generator. Said generator is in this instance formed of a frame 32, pivoted by trunnions 33 to the lower portion of the bed of frame 7, and carries at its rear. end an adjustable weight 34 and on its front end a treadle 32, by which the operator can tilt the frame 32 upon its trunnions. Cords 30, connected to the frame 32 near its rear weighted end, pass ITO about pulleys 31 on the bed 7 of the machine and are attached to a bar or yoke 29, having a central recess adapted to engage and transmit its approximately constant pressure upon a projection (as the shaft of set-screw 40) on the tool-holder 35. By this means the weight 34: normally depresses the rear end of the frame 32, the draft of which is transmitted, through the cord 30, yoke 29, and set screw 40, to the tool-holder, and so brings the templet 39 into contact with a portion of the guide-plate 27, where it protrudes below the guide-plate carrier 25, and thus holds the templet under a constant pressure in contact with said plate despite the small movement necessary to be made in the tool-holder during the grinding operation. By moving the weight 34 outwardly or inwardly upon its frame (for which purpose the frame is shown as conveniently notched) greater or less pressure, as desired, can be exerted between the templet and guide-plate. By a downward pressure upon the treadle 32 the operator can, however, diminish or wholly relieve the tension and draft of the aforesaid pressuregeneratormechanism. This means of dimin ishin g the substantially constant, but adj ustably intent pressure of such uniform-pres sure generatorI shallherein term a pressurediminisher. The templet and guide-plate having been brought into contact, and also, preferably, automatically pressed together, as previously described, the tool 36 or other article to be ground is next brought from its aforesaid bare contact with the grindstone 3 in actual operation therewith as follows: either by feeding the grindstone with its shaft and bearings 67 bodily up to the tool, or by moving the guide-plate carrier 25 toward the grindstone. In the former case the auxiliary frame 67, carrying with it the bearings of the grindstone-shaft and the swash-motion 1n echanism aforesaid, is traversed upon its ways along the face of the bed '7 bya screw 76, engaging a nut on the auxiliary frame and rotated, through the intermediacy of a pair of bevelgears 7 7, by a hand-wheel 7 8, the screw '76 being of course suitably collared for this purpose against endwise movement. Otherwise, where the guide-plate carrier is used, such movement is readily effected by the screw 26, which, as before stated, engages a nut on the guide-plate carrier and rotates without end movement in a bearing on one of the supporting post-heads 19 Rotation being then imparted to the grindstone, the toolholder 35 is moved about by the operator on the table 10, preferably by means of a handle 4-1:, and as each portion of the surface of the templet successively comes in contact with the abutting surface of the guide-plate the corresponding portion of the piece of work 36 is subjected to the action of the grindstone. In this manner the end of the piece of work 36 adjacent to the grindstone is ground so as to be brought to shape corresponding with that of the templet, and also to bear the desired relation to the body of the piece of work determined bythc relative adjustment thereof and of the templet.

During the operation thus described the reciprocating movement of the grindstone, which may be invoked by the swash-motion mechanism, serves to promote the maintenance of a truly cylindrical grinding-surface by causing each portion of the width of the face of the grindstone to be brought in con tact with the article to be ground, thus throwing the maximum wear upon any comparatively projecting parts of the stone or shearing off such projecting parts and enabling grinding to be effected with stones which may be originally uneven and lumpy, but which in use in my improved machine, as thus described, become gradually reduced to cylindrical form.

IVith tools which are, speaking in relation to the direction of the grindstones rotar T motion, thin, the above method of operating my improved grinding-machine is substantially all that is required. I will, however, here point out that with tools which are thick and in which exact temper and absolute absence of water-cracking is essential my improved grinding-machine, as above described, is also designed to attain as far as practicable the useful results of the ordinary system of grinding tools, in which the tool is held in the hand of the operator, and also to avoid the objections incident to the practice of such system. In order to make this clear, it would be proper here to make a short digression and state that it is well known to those skilled in the art that in order to rapidly remove metal by grinding it from a surface the grindstone should be in contact at any one instant with only a point, short line, or comparatively small portion of said surface. If, for example, apiece of metal be held rigidly against the face of a grindstone, preserving the same relative position to the stone throughout the operation of grinding, save only that it is fed toward the stone, at a rate proportioned to that at which the metal is ground away, the action will be exceedingly slow, and the more closely the surface of the object which is being ground fits or assumes the shape of the grinding-surface of the stone the slower will be the rate at which the metal is removed, the energy of the stone and the work of friction being almost entirely expended in heating the object being ground on the grindstone. In the practice of handgrinding the natural tremor of the operators hand which holds the object being ground, and, in fact, the skill of a skilful grinder to continually move the object relatively to the surface of the grindstone, prevents it such coincidence and the damage arising from the resultant heating. To the like end the construction of the machine, as hercinbefore described, is such as to enable this change of contact-point between the object and the grindstone to be readily and effectively carshown in Figs. 5 and 7 preferably equipped with a cross-head, and so the tool-holder can be either swiveled about in the plane defined by the table or it can be manipulated so that one or the other side or end of the tool-holder can be raised or lowered to change the points of contactnot only of its own bearing, but

also of that of the work where it comes in contact with the acting plate of the guide table. The rocking movement of the toolholder is thus invoked for the sake of presenting small and successive contact-surfaces or even a mere succession of points between the work and grindstone,and may further be facilitated by placing a piece of wire between its lower side of the supporting-surface of the table upon which it preferably then may be rocked, whilethe roughing or heavier portion of the grindingis being performed. Further, the useful effect of a change of the relati ve position of the work andgrindstone above referred i to being most advantageously exerted duringthe period when it is desiredto grindthe greatest amount of metal from the tools the grinding at such period may also be facilitated by bringing the guide-plate 27 and the acting face of the grindstone 3 so closely together that when the tool 36 touches the stone a small space will be interposed between the templet 39 and the surface of the guideplate. Such space better permits the toolholder to be moved up and down, (vertically tilted,) as aforesaid, for a short distance and in such wise as to be rapidly moved from side to side by the operator without withdrawing allthe tool-face about to be ground from the range of the stone. Thus a portionof the surface of the tool being continuously in contact with the grindstone, the close proximity of the guide-plate to the templet still renders it impossible to grind thetool to any material variation from theshape of the templet; and in this instance, whennearly the desired amount of metal has been removed from the surface of the tool, the guide-plate 27 can be gradually brought closer to the templet and the foot of the tool-holder reposed fiat along the supporting-tableforthefinalpassages. Then a short period of contact of the work with the stone sufficesto finish the surface operated upon to accurate conformity with the face of the templet, for the same is continuously con.- tactedwith the said guide-plate as a trace.

The machine being designed more particularly for grinding tools to be used for cutting and boring metal in lathes, planers, boringmills, or other machinery, it would be better, before proceeding to a more minute description of the tool-holders suitable. for holding them with their appropriate tern plets in proper adjustment, to give a brief explanation of the functions and structural principles" of such tools.

Tools used in cutting wood or metals may be regarded as wedges, the portion of the tool by which the cutting or straightening is effected being bounded by two or more surfaces, (either curved or approximately plain, as the case may be,) which intersect in a line known as the cutting edge of the tool. In one class of tools, such as axes, knives, scissors, &c., one or more of the surfaces which form the wedge presses against the shaving, chip, or that part of the substance which it is desired to remove, while the other surface of the wedge presses against the main body of the substance.

In other classes of cutting-tools, such as tools for lathes, planers, boring-mills, or the knives of many Wood-planing machines, the chip or shaving which is being removed from the piece of Wood on which the tool operates alone receives the pressure of one of the surfaces forming the wedge, while the body of the piece from which the shaving is being cut is touched only by the cutting edge of the tool, and the angle which the surface of the wedge which does not press upon the shaving or chip makes with the surface of the work from which the chip is being removed is called the clearance angle of the tool. As the surface adjacent to the clearance angle is frequentlya curved surface, and the surface of the object which is being cut is also frequently curved, the clearance angle of the tool at any point may be more properly defined as the angle made by a tangent to the clearance-surface at that point with a tangent to the surface being cut at the same point. The surface of the wedge which presses against the shaving or chip is variously term ed top surface, the face of the tool, or the lip-surface of the tool.

In order to produce the most effective re sults, it is generally desirable in finishin g cutting-toolsthat parts at least of the surfaces above mentioned, which intersect to form the cuttingedge of the tool, should bear a definite relation one to another and in many instances to one or more of the remaining surfaces of the tool. Thus, for example, in the first of the above classes of tools, such as an ax or chisel, the angleclose to the cutting edge of the surfaceswhich intersect in the cutting edge should be a definite angle, de pendent upon the class of work forwhich the tool is intended, because if too acute the tool is liable to break, while if not sufficiently acute the cutting-action of the tool is impaired' In the second class of tools, as lathetools, &c., it is important that each. should have a certain definite clearance angle, dependent upon the class of work it is intended to perform, and all tools designed for the same specific description of work should have approximatelythe same clearance angle. It is further important in tools of this class that the angle made bythe face or lip-surface of the tool with the clearance-surface should be, as nearly as practicable, constant in all tools intended for exactly the same class of work. It is also desirable in many cases that the cut-ting edge of the tool should hold a definite position to one or more of the other surfaces of the tool besides the lip and clearance surfaces.

It will be obvious that in grinding cuttingtools having curved cutting edges, as is the case in the second class above mentioned, the several curves formed by successive grinding operations cannot hold the same relation in every respect to the body of the tool. It is practicable and desirable, however, for the proper working of the tool so to grind it that these several curves shall have, as nearly as may be, the same form, and that their cenfor line shall make equal angles, respectively, with the body of the tool. It may be further noted that in the majority of cutting-tools, while it is important that for a short distance back of the cutting edge the curves of the clearance or the top surfaces of the tool should nearly coincide with tangents drawn to said surfaces at the cutting edge, it is permissible and frequently desirable that as said surfaces recede farther and farther from thecutting edge they should deviate more and more from lines tangent to them at the cutting edge.

In dressing or finishing metal-cutting tools so as to attain the best performance of their function there is therefor an ideal or standard form, and the most satisfactory and effective results of uniformly grinding such tools when of similar character for the same class of work to a shape corresponding to that of a determined standard templet will also appear from the foregoing explanation. More over, as previously described, the successive application in the operation of the above-described machine of different portions of the templets 39 to the contacting surface of the guide-plate 27 by the movement of the toolholder 35, especially in the latter stages, (where the initial rocking and tilting motions which are effected to promote the rapidity of the grinding action by the successive presentation of a series of points, lines, or minute contacting surfaces are abandoned and the final form determined by the seating of said tool-holder fiat-footed upon the surface of the table 19, whereon it is then swiveled or otherwise trained, as above set forth, insures the coincident application of corresponding portions of the tool 36 to the acting surface of the grindstone 3, and in order that such governing action of the templets shall be properly exerted upon tool after tool of a series of similar tools the device above alluded to as forming the subject-matter of an application for aUnited States patent, lately filed by me, is again and especially referred to, for by it the templet and tool may be accurately adjusted in their normal relative positions in the tool-holder, whereby such device will be seen to be not only a convenient adjunct to my present invention, but especially adapted for conjoint use therewith.

Reverting again to the operation of the grinding-machine, as above illustratively described, it is in many instances only required that the cutting edge of the tool shall be at a given'angle to one or more surfaces of the tool, and in such case, if the surface of the templets which comes in contact with its abutment, (which is in this instance the extended tracing-surface of the guide-plate 27, Figs. 1 to 4, inclusive,) it has the proper angle to the surface of the tool. Moreover, not only is it not essential to the production of the form that the templet should stand immediately over the tool which is to be ground, but it may and indeed often must be adjusted so as to be in front, to the rear, or on either side thereof, and by altering the angle of the grinding-table 19 with reference to the stone, as its above-preferred adjusting equipment permits, a cutting edge may be ground on the tool by my said machine which shall hold the desired relation to the body of the tool. In the case of tools having curved cutting edges it is desirable, as a general rule, that the templet should be of the exact size and shape of the cutting edge of the tool which it is desired to grind. It is, however, sometimes desirable that the surface of the templet, while curved similarly to that of the desired cutting edge of the tool, should be either slightly larger or slightly smaller than the latter.

In the tool-holder 35 (shown in Figs. 5 and 7, which are in point of fact enlargements in perspective and side elevation, respectively, of the tool-holder indicated in broken-line outlines in Fig. 1) the tool is rigidly clamped to the body of the tool-holder, while the templet '39 is attached to a movable slide 41, which slide, in its turn, is supported by another movable slide 42, having a motion transverse to the former. By means of these two movable slides it is obvious that the templet may be brought into a proper relative position to the tool 36 aforesaid, and then by means of the binding-stud 43 clamped fast. That is to say, these figures illustrate a toolholder of my improved sort having means for adjustably securing a templet and tool in universal con-plane adjustment. In a toolholder of such construction it is not absolutely essential that the two slides should be used for bringing the templet into proper relative adjustment to the tool, as the templet may be attached to the slide 42 and moved therein from side to side, while the tool 36 is moved backward and forward in the toolholder until the tool and templet occupy their proper relative positions, and then clamped fast, the means for said clamping being for the slide 42 the stud 4E3 aforesaid, and for the tool 36 by having its body a driving fit for a corresponding combined seat and slotted guideway in the upper surface of the foot of the tool-holder 35, as will be readily seen on referring to Fig. 7.

In the modification of the tool-holder shown in Figs. 6 and 8 the piece of work or tool 36 is clamped by a shoe 37 and a set-screw 50 upon a block 47, which is journaled at one- .thread of a bolt 55, which is fixed inihe shoe 37, and passes freely through a segmental slot 49 in a standard 51, formed upon the toolholder, the shoe 37 bearing against one side of the standard 51 and the clamping-nut 52 against the other. In these figures the tem-. plet 39 is secured by a set-screw 40, formed in a projection 46 on one side of the standard 51, and the tool-holder is provided with a handle 44 and a side-motion stop 45 in the form of a downwardly-proj ectin g pin, as in the instance first described. Fig. 6 shows the above-described modification of the tool-holder in the act of presenting a corner of a tool 36 to the grinding-face of the grindstone 3. At such time the normal pressure of the uniform-pressure generator shown in Fig. 1 (consisting of the frame 32 and adj ustably-securable weight 34, applied by means of the cords 30 and yoke 29) may be presumed to be in excess of the amount which it would then be proper to apply to such a corner of a tempered tool undergoing the grinding action of the stone 3, and it is presumably an appropriate time for the operator to take advantage of the pressurediminishing device, consisting of the treadle 32 with the connecting-frame 32, and thereby to in whole or part relieve the pressure due to an unimpeded action of the aforesaid uniform pressure generating mechanism. When, however, in the grinding operation the tool-holder 35 (shown in Figs. 6 and S) is swung around so as to bring the substantially squarely transverse or front cutting edge of the tool 36 in line with the face of the stone 3, it will be appropriate, especially in the roughing stages, or when the tool-holder should, as above described,'be rocked or tilted to a certain degree upon the supporting-surface of the table 19, for the operator to then allow the full draft of said pressure-generator to take effect upon the bearing stud 40 through the transmitting device, consisting of the cords 30 and yoke 29. In the final stages, where the tool-holder is bedded flatfooted upon the supporting-surface of the table 19, I would, in order to prevent what is known to grinders as water-cracking, in all cases recommend such use of the pressurediminishing mechanism as may effect the lightest possible contact-pressure between the tool and grindstone, which then have their maximum extents of surfaces in contact.

Upon inspection of Fig. 1 it will be obvious that as the templet 39 is at any time either in actual contact with its abutting surface upon the guide-plate 27 or distant therefrom by an amount equal to'the amount of its relative adjustment or to the feed determined either by the manipulation of the screw 26 or that of the manipulating-gears 78 77, Fig. 3, it will be impossible for the tool to dig in, even if a considerable protuberance on the surface of the grindstone 3 should strike the tool, the stone being revolved downward 'or toward the tool, as is best to be done for the sake of carrying in the cooling-water which falls from the feed-pipe 76 between the grind ing surfaces. In fact, all that can occur from such a collision is, as hereinbefore in part referred to, either a shearing offof said protuberance from the surface of the stone or a backing out in a safe direction, not only of the tool 36, but also of the tool-holder 35, the direction of suchbacking-out motion being in most cases determined by a resultant of the pressure of collision, the draft of the pressure-transmitting.yoke 29, and the reactionary strains due to the fulcruin'or abut ment of the templet 39 upon the guide-plate 27.

While it is more desirable that the saddle 17 should be, as shown, separate from the main frame and adjustable thereon, it is not essential in all cases that such should be so, and the saddle may, if desired, be either bolted rigidly to the main frame or cast integral therewith. Such a modification is illustrated in 17 Fig. 12, wherein the saddlejournal above alluded to is in the form of a bolt-head, projecting from said saddles upper surface and adapted to register with its appropriate bearing 20 in the under surface of the table 19, as shown by the broken-away portion of said table in Fig. 12 when assembled. In this figure the templet or former 39, which determines the profile of the tool, is shown placed below the tool, for which reason the abutment-plate 27 is also represented as passing below the tool, in which position it can of course equally well serve as a reading-surface, at any part of which the profile-defining templet may be contacted and caused to trace its shape by the action IIO of the stone upon a corresponding portion of 15 the surfaces of the tool. However, so far as the guide-plate 27 is in this case desired to act as a fulcrum, in the case of collision with the grindstone protuberances, it is of course essential to reverse the rotary movement of the stone, such reversal being indicatec by the arrow, included in the dotted outline of the fragment of the grindstone shown in Fig. 12. The templet is here shown with the cruciform body, a portion of which is interrabbeted with the surface of the tool holder and provided with an adjustment-screw 45, prevented from endlong movement with relation to said interrabbeted part of the templet, the latter being thereby adapted to be adj nsted and held in positions transverse to the tool 36; The tool is in this instance also adapted to be adjustably protruded from a cleft-holder post by means of a key passing through transversely-pierced slots. Moreover, the lower face of the loose and detachable tool-holder is in this case so far modified as to be grooved or slotted out with a single groove and the upper surface of the table 19, near the guide-plate 27, is provided with an upstanding fixed pin 45that is to say, the machine is here illustrated as provided with a side-motion stop the converse in form yet equivalent in action to the one illustrated in Figs. 2 and 5.

In Fig. 9 I have shown the grindstone carried upon its shaft in bearings 6, formed in vibratory auxiliary supports 67, instead of in the rectilinearly-adjustable auxiliary frame 67, as is the case in Fig. 1. As a means for reciprocating the grindstone and its shaft endwise through the vibratory bearings 6, I have shown a broad-faced pulley attached to one extremity of said shaft and a scrollcam 11, rigidly attached to the other, and to the frame 07 I have connected by a suitable bracket a friction ally-provided reading-finger 10, or substantially the means for producing a swash motion in a grindstone, specifically described in the United States patent to John G. Baker, No. 182,882, of October 3, 1876, and which therefore does not need further comment from me save only to state that as it has no capacity for adjustably varying the throw of the endwise-reciprocating mechanism, even on occasion of discontinuing it, I much prefer to associate the other new and useful features of my invention with the sort of reciprocatingmechanism illustratively described in Figs. 1 to 4, inclusive.

I11 Fig. 9 I have shown the guideplate carrier rigidly bolted to the main frame or pedestal 7 of the machine. I have also represented in this figure the saddle 17 as formed of two similar halves or plates rigidly bolted to the outer side of the said pedestal; their table-bearin g being also split and separated in this case, require the cylindrical projections or hearing 20 of the table 19 to take the form of trunnions. The mechanism for holding the table down to said saddle-seats is, however, unchanged from that already hereinbefore described, save only that in addition to exerting a downdraft upon the rear of the table I provide that the rear screw shall here pass through a swiveling nut, which is attached by suitable lugs to the main frame 7. In order to adjust and secure the auxiliary frame 67 I contrive that it may be rocked about its pivot-shaft 67 (to which it is collared endwise by terminal nuts) by means of a feed-screw 07, which, being journaled without end motion to a lug projecting from the front end of the pedestal 7, passes through a nut swivelingly connected to a yoke which forms the connection between the arms of the said frame (37 by passing in the manner of a bridle about the sides and front of the frame 7. Also, in order to equip the machine with a modified form of pressure generating and diminishing devices, I attach to any convenient adjacent fixed part (as the adjoining ceiling of the room. where the grinding-machine is situated) a long spiral spring, as indicated by the end of such a spring 34:, Fig. 9, and, attaching to it, as by a hook and eye, draftcords 40, direct them by guide-pulleys 31 to the toolholder draft-yoke 29, and thus equip it with a substantially equivalent constantpressure generator to that shown in Fig. 1, save only that in this case I make no provision for a range of intensities, such as I provided for in the case shown in Fig. 1. In order to diminish the pressure which may be developed by the spring 3 1, I attach to the center of the yoke 29 a cord 32*, and, as by a guidepulley, as shown in Fig. 9, lead it to any convenient point, where I equip it for operation, as with a handle 32.

In Fig. 11 I have shown as a modification of the constant-pressure generator and its transmitting devices a stand-pipe 34 which, being filled with water and operatively connected, as by opening an intermediate connected cock with a ram-cylinder 34 is obviously operative to exert a pressure upon the admission side of its piston, and by means of its piston-rod and pitman 30 exert a pressure upon the yoke 29 which in this instance by means of a pivot 29 and one or more suitably-placed pivot socket-holes in the table 19, I contrive as a lever by means of which,when provided with an appropriate series of pitman engagements, as the notches 29, may be conveniently used as a device for not only imparting but also of varying the intensity of the pressure generated by the column of water in the stand-pipe 24 through the medium of the open cock and ram mechanism aforesaid.

In Fig. 10 I have shown the auxiliary or bearing frame 67 fixed to the main frame of the machine 7, and the grindstone-shaft 2, which passes through them, presumably neck down, in such manner as to prevent endlong reciprocation, or substantially in the form which it would be compelled to move in should a pair of pins be inserted through a pair of the holes in the series 16 of the reciprocating mechanism shown in Figs. 1, 2, 3, and 4. I also show in this modification that it is within the purview of my invention to have a noncylindrical or grooved acting face to the grindstone. (See 3%) However, in order to associate herewith the other leading features of my invention, it then becomes necessary to have a correspondingly-modificd representtation of the grindstones acting-face in the templet-abutting surface of the guide-plate. For this reason I have shown in connection with the groove 3" a corrugated guide-plate 27, said plate being supported by standards 19, secured by T-headed bolts engaging in T-headed slots formedin the upper faceof the main frame 7, and substantially transverse to a plane passed vertically through the grindstone-shaft.

In Fig. 11 I have shown a modification of the pressure-transmitting mechanism used for advancing the: tool-holdergwith its'appropriately adjusted templet and tool to their respective duties in'connection with the guide-plate and grindstone. It consists in substituting for the single lever shown in Fig. 11 a series of levers, one acting upon the other and the last upon the fulcrum 7 2, and

acts in a manner so readily understoodas to need no other description than that which the figure itself graphically conveys.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent, is i i 1. The combination in agrinding-machine, of a frame or bed, a grindstone fixed upon a shaft, mounted in bearings thereon, mechanism substantially as described, for reciprocating the grindstone-shaft in its bearings during its rotation said mechanism being provided with meansfor varying the end movement of the grindstone-shaft, consisting of a lever operatively connected with said shaft andhaving a shiftable fulcrum, whereby the relative length of the lever-arms may be changed at will; substantially as and for the purposes hereinbefore described.

,2. The combination in a grinding-machine of a frame or bed, a grindstonefixed upon a shaft, mounted in bearings thereon, an independent counter shaft, as 9, journaled in bearings on the frame, a cam fixed upon the counter-shaft, a lever adapted to bear on said cam at oneof its ends and having a longitudinal series of holes for pivot-pins 0r bolts, a lever-bearing fixed to said frame, and having a corresponding series of holes,a pivot or bolt, adapted to fit anyone of the series of holes in the lever and lever-bearing, a shoe pivoted to the lever aforesaid, and adapted to fita circumferential groove, in the grindstone-shaft aforesaid, and a subsidiary bolt or pin operative on occasion to be passed.

through any unoccupied registering pair of said lever and bearing holes and lock said lever, substantially as and for the purposes hereinbefore described. i

3. The combination in a grinding-machine of a frame or bed, a grindstone fixed upon a shaft, mounted in bearings thereon, an independent counter-shaft, as 9, adapted to actuate mechanism, substantially as described for reciprocating the grindstone-shaft endlongin its bearings during its rotation and mechanism operative-upon the disconnection of said counter-shaft driver to maintain said grindstone-shaft without endlong movement in its said bearings, substantially as and for the purposes hereinbefore described.

i 4. The combination in a grinding-machine of a frame or bed, a grindstone fixed upon a shaft, mounted with capacity of end movement in bearings on the frame, and a series of alternately-fixed and movable telescopic covers, inclosing the portions of 'thegrindstone-shaft journals exterior to the bearings thereof, substantially as set forth.

5. The combinationjna grinding-machine of a frame or bed, a grindstone fixed upon a shaft,mounted with the capacity of endmovement in bearings thereon, a series of covers, each of which is open at one end and secured at the other to the grindstone-shaft concentrically therewith, and at or near one end of the journal thereof, and a series of similar covers each secured to a fixed support, ad-

jacent to one end of the grindstone-shaft journal, and fitting freely circumferentially against one of the covers which are secured to the shaft, substantially as set forth.

6. The combination in a grinding-machine of a frame or bed, a grindstone fixed upon a shaft, mounted with the capacity of end movement in bearings thereon, and a series of alternately-fixed and movable telescopic covers inclosing the portions of the grindstone-shaft journals exterior to the bearing and provided with rims or flanges at theiradjacent ends, substantially as set forth.

7 The combination in a grinding-machine of aframe or bed, a grindstone fixed upon a shaft, mounted in bearings thereon, a grinding-table connected to the frame, a tool-holder supported loosely upon the table, means connecting it to the table, whereby it is capable of free movement by sliding, swiveling or tilting, and a guide-plate, substantially as set forth.

8. The combination in a grinding-machine of a frame or bed a grindstone fixed upon a shaft, mounted in bearings thereon, a grinding-table connected to the frame and having a tool-holder-supporting surface as described, a guide-plate supported adjacent to the grindstone, a tool-holder having a foot conforming to the supporting-surface of said table and adapted to be supported thereon with the capacity of free movement, in either swiveling or tilting as described anda templet or former fixed in the tool-holder in position to bear against the guide-plate, and regulate the movement of a piece of work, secured in the tool-holder, relatively to the surface of the grindstone, substantially as and for the purposes hereinbefore described.

9. The combination 1n a grinding-machine of a frame or bed, a grindstone fixed upon a i shaft, mounted in bearings thereon, a grinding-table connected to the frame and having a tool-holder-supporting surface as described, a guide-plate supported adjacent to the grindstone, a tool-holder having a foot conforming to. the supporting-surface of said table and adapted to be supported thereon with the capacity of free movement, in either swiveling or tilting as described, a templet or former fixed in the tool holder in position to bear against the guide-plate and regulate the movement of a piece of work and secured in the tool-holder relatively to the surface of the grindstone, and a mechanism composed of a pressure'generator and a pressure-transmitter for exerting approximately uniform pressure between the grindstone and the object being ground in the operation of grinding, substantially as set forth.

10. The combination in a grinding-machine of a frame or bed, a grindstone fixed upon a shaft, mounted in bearings thereon, a grinding-table connected to the frame,a guide-plate supported adjacent to the grindstone, a toolholder having a foot conforming to the surface of such grinding-table and adapted to be supported thereon, with capacity for free swiveling and tilting or rocking movements as described, a templet or former, fixed in the tool-holder in position to bear against the guide-plate and regulate the movement of a piece of Work secured in said tool-holder relatively to the surface of the grindstone, a mechanism composed of a uessure-generator and a pressure-transmitter adapted to exert approximately uniform pressure between the grindstone and the object being ground, in the operation of grinding, and a pressure-diminishin g mechanism adapted upon occasion, to either decrease or Wholly relieve the pressure of the aforesaid mechanism between the grindstone and the object being ground, substautially as set forth.

11. The combination in a grinding-machine of a frame or bed, a grindstone fixed upon a shaft,mounted in bearings thereon, a grinding-table connected with the frame, a guideplate supported adjacent to the grindstone, a tool-holder, having a foot substantially conforming to an equal area of said grinding-table and adapted to be supported thereon with the capacity for free swiveling and tilting as described, a templet or former fixed in said tool-holder in position to bear against said guide-plate and regulate the movement of a piece of work, secured in the tool-holder relatively to the surface of the grindstone, a pressure-generator which is adjustable to impart different degrees of pressure each degree bein g of a substantially uniform pressure in itself and a pressure-transmitter operatively connecting said generator and said toolholder, substantially as and for the purposes hereinbefore described.

12. The combination in a grinding-machine of a frame or bed, a grindstone fixed upon a shaft, mounted in bearings thereon, a grinding-table connected with the frame, a guideplate supported adjacent to the grindstone, a tool-holder, having a foot substantially conforming to an equal area of said grindingtable and adapted to be supported thereon with the capacity for free swiveling and tilting as described, a templet or former fixed in said tool-holder in position to bear against said guide-plate and regulate the movement of a piece of Work, secured in the tool-holder relatively to the surface of the grindstone, a pressure-generator which is adjustable to impart different degrees of pressure each degree being of a substantially uniform pressure in itself and a pressure-transmitter operatively connecting said generator and said toolholder, and a pressure-diminisher operative to relieve the pressure produced upon said tool-holder by said pressuregenerator and transmitter, upon occasion, substantially as set forth.

13. The combinationin a grinding-machine of a main frame or bed, a grindstone fixed on a shaft, mounted in bearings thereon, a grinding-table connected with the frame, a guideplate supported adjacent to the grindstone, a frame as 32, pivoted to the main frame, a weight, operatively connected to said frame and tending to vibrate the same about its axis, a tool-holder having a foot adapted to the surface of said grinding-table and adapted to be supported thereon with free swiveling and tilting capacity as described, a templet or former secured in said tool-holder, in position to be brought into contact with said guideplate, means for shifting the point of application of said weight at varying distances lengthwise of the frame 32, and a flexible connection by which said tool-holder may be coupled to said frame, substantially as and for the purposes hereinbefore described.

14:. The combination in a grinding-machine of a main frame orbed, a grindstone fixed on a shaft, mounted in bearings thereon, a grinding-table connected with said main frame, and having a substantially plane supportingsurface, a tool-holder having a substantially plane foot adapted to be supported upon said table, a tool and a templet adapted to be secured in the tool-holder and a guide-plate adjustable toward and from the grindstone, substantially as set forth.

15. The combination in a grinding-machine of a main frame or bed, a grindstone fixed on a shaft, mounted in bearings thereon, a grinding-table connected With said frame and having a substantially plane supporting-surface, a tool-holder having a substantially plane foot, adapted to be supported on said table, with freedom for tilting and swiveling as de scribed, and to have secured therein a tool and a templet, said tool and templet, a guideplate carrier, adjustably secured upon said grindstone-table in such manner as to be fed to and from the grindstones acting-face, and a guide -plate secured to said carrier, and adapted to afford an abutment tracing-surface against Which said templet may be brought to bear when the tool-holder is supported upon said table and operatively presenting said tool or piece of Work to the grindstone, substantially as and for the purposes hereinbefore described.

16. The combination in a grinding-machine of a main frame or bed, a grindstone fixed 011 a shaft, mounted in bearings thereon, a grinding-table adjustably connected to said main frame, so that its angle may be varied relatively to the surface of the grindstone, a guide-plate carrier, fitted in guide-bearings on the grinding-table, and adjustable toward and from the grindstone, and a guide-plate IIO fitting in guide-bearings on the carrier and adjustable toward and from the surface of the grinding-table, substantially as set forth.

17. The combination in a grinding-machine of a main frame or bed, a grindstone fixed'on a shaft, mounted in bearings in an auxiliary frame, which is adjustable upon the main frame, a grinding-table which is mounted on the main frame and adjustable toward and from thegrindstone, a loose and detachable tool-holder adapted to be supported upon the table, and a guide-plate fixed in a support adjacent to the grinding-table; substantially as and for the purposes hereinbefore described.

18. The combination, in a grinding-machine, of a main frame or bed, a grindstone fixed on a shaft mounted in bearings there on, a grinding-table connected to the main frame, and adapted to support a loose and detachable tool-holder, and a guide-plate secured in a carrier which is adjustable upon the grinding-table toward and from the grindstone, substantially as set forth.

19. The combination, in a grinding-machine, of a main frame or bed, a grindstone fixed on a shaft mounted in bearings thereon, a grinding-table connected adjustablyto the main frame so that its angle may be varied relatively to the surface of the grindstone, a guide-plate carrier fitting in bearings on the grinding-table and adjustable toward and from the grindstone, and a guideplate fitting in the carrier and adjustable toward and from the surface of the grindingtable, substantially as set forth.

20. The combination, in a grinding-machine, of a main frame or bed, a grindstone fixed on the shaft mounted in bearings thereon, a grinding-table connected to the main frame, a gu ide-plate supported adjacent to the grindstone, abar or frame pivoted to the frame and carrying a weight at or near one of its ends and a treadle or foot-plate at the other, a removable and otherwise relatively free tool-holder supported on the grinding-table, a templet or former secured in said tool-holder in position to be brought in contact with the guide -plate, and a flexible connection by which the tool-holder may be coupled to the weighted end of the pivoted bar or frame, substantially as set forth.

21. The combination, in a grinding-machine, of a main frame or bed, a grinding-table connected thereto, a loose and detachable tool-holder, means connecting it to the table whereby it is capable of free movement by sliding, swiveling or tilting, a guide-plate fixed in a support adjacent to the grindingtable, and a grindstone fixed on a shaft mounted in bearings in an auxiliary frame which is movable on the main frame relatively to the grinding-table; substantially as set forth.

22. The combination, in a grinding-machine, of a main frame or bed, a grindstone fixed on a shaft mounted in bearings thereon, a grinding-table journaled upon a saddle or bearing casting on the mainframe, a guideplate fixed in a support adjacent to the grin d ing-table, and adjusting screws connecting the grinding-table at each of its ends to the saddle-casting and adapted to vary its inclination relatively thereto, substantially as set forth.

23. The combination, in a grinding-machine, of a main frame or bed, an auxiliary frame adjustable in position thereon, a grindstone fixed upon a shaft which is mounted with the capacity of end movement in bearings in said auxiliary frame, a grindingtable journaled adjustably on a saddle or hearing casting fitted to move on guides or ways toward and from the grindstone, a guide-plate fitting in a support adjacent to the grindingtable and adjustable toward and from the grindston e, a weighted baror frame pivoted to the main frame, a removable tool-carrier supported on the grinding-table, a templet or former secured in the tool-holder in position to be brought in contact with the guide-plate, and a flexible connection by which the toolholder may be coupled to the pivoted bar or frame, substantially as set forth.

24. The combination in a grinding-machine, of a main frame or bed, a grindstone fixed on a shaft mounted in bearings thereon, a grinding-table connected to the main frame, a guide-plate fixed in a support adjacent to the g1-inding table, a removable tool-holder supported on the grinding-table, a templet or former secured in said tool-holder in position to be brought in contact with the guide-plate, a frame composed of a pair of bars pivoted by trunnions to the main frame and having a treadle or foot-plate at one of its ends and an adjustable weight at or near its opposite end, a pair of guide-pulleys journaled on the main frame,and a pair of cords passing around said pulleys and connected at their opposite ends to the weighted end of the pivoted frame and to a yoke or bar fitted to engage a projection on the tool-holder, substantially as described.

25. The combination, with a grinding-machine having a main frame or bed, a grindstone fixed on a shaft mounted in bearings thereon, a grinding-table connected to the main frame and a guide-plate fixed in a support adjacent to the grinding-table, of a loose and detachable tool-holder carrying a templet or former and fitted to receive the piece of work to be ground, and a device for adjusting the templet and piece of work in proper position in the tool-holder to admit of the templet being brought into contact with the guide-plate and the piece of work into contact with the grindstone, when the toolholder is rested upon and shifted in position upon the grinding-table of the machine, and means connecting it to the table, wherebyit is capable of free movement by sliding, swiveling or tilting, substantially as set forth.

26. The combination with a grinding-ma chine having a grinding-table, of a loose and detachable tool-holder having a flat foot and a receptacle for a tool or other article to be ground, means connecting it to the table, whereby it is capable of free movement by sliding, swiveling or tilting, and a templet or former fitting adjustably in the tool-holder, and an adjusting device for facilitating the location of the templet and a tool inserted in the holder into proper relative position for subjecting the tool to the action of the stone of a grinding-machine, substantially as set forth.

27. The combination in a tool-holder for grinding-machines, of a plate or bed constructed to conform to, swivel about and to rest loosely and detachably upon a grindingtable, a tool-support and a templet-receptacle connected to said bed, and means for securing a tool and a templet in their respective positions in the support and receptacle, substantially as set forth.

28. The combination in a tool-holder for grindingmachines, of a plate or bed constructed to swivel about and to rest loosely and detachably upon a grinding-table, a te1nplet secured to said bed, a t0ol-support, and a device for securing a tool in position in said support, substantially as set forth.

29. The combination, in a toolholder for grinding-machines, of a tool-support, a templet-receptacle, means for securing a tool and a templet in their respective positions in the tool-holder, and a side-motion stop, substantially as set forth.

30. The combination, in a tool-holder for grinding-machines, of a tool-support, a templet-receptacle, means for securing a tool and a templet in their respective positions in the tool-holder, a sidemotion stop, and an operating-handle, substantially as set forth.

FREDERICK XV. TAYLOR.

Witnesses:

CLARENCE M. CLARK, THos. R. REED. 

